With over 30 years of satellite-based positioning experience and continuous research, we are able to offer market-leading innovations, quality and a wide range of services. These services include independent sub-decimetre level services (Starfix.G4/G2 and Starfix.XP2), centimetre level services (Starfix.G2+) and sub-metre level services (Starfix.L1)

Starfix® can be used to support a number of offshore activities, such as seismic surveys, offshore construction vessels, survey operations, pipelay and cable lay activities, dive support, FPSO installation and monitoring.

Our Starfix.G4 service is a GPS, GLONASS, Galileo and BeiDou positioning system that is based on orbit and clock corrections generated from Fugro's own expanded network of multiple system reference stations. Starfix.G4 utilises Precise Point Positioning (PPP) technology, which distinguishes itself from the traditional differential approach as satellite errors are not lumped together but estimated at source on a per satellite basis. The GPS, GLONASS, Galileo and BeiDou orbit and clock corrections are computed separately, free of ionospheric and tropospheric effects.

The G4 service uses all available satellites to produce a composite position, offering a number of advantages:

Additional satellites confirming the calculated position build confidence and reliability.

Better resistance to ionospheric scintillation effects which tend to affect a particular part of the sky.

Possibility to bridge periods of bad geometry for each of the separate systems.

Further positional enhancements are undertaken in our software resulting in positional accuracies of better than typically 10cm (2σ) in both the horizontal and vertical planes.

The Starfix.G2+ service is an ultra-precise GPS and GLONASS Global Positioning Service, using Clock and Orbit Corrections enhanced with carrier-phase corrections from the Fugro Starfix.G4 Network.

Starfix.G2+ is an enhancement of our highly regarded Starfix.G4 service and utilises advanced GNSS augmentation algorithms developed in-house by our leading GNSS augmentation experts.

The code and carrier-phase signals transmitted by GPS and GLONASS satellites are monitored globally by Fugro’s worldwide network of reference stations. These observations are processed in real-time using our proprietary algorithms to generate precise corrections which are used to augment the standard signals broadcast by GPS and GLONASS satellites. Corrections are received via seven high-powered communications satellites, providing at least two independent Starfix.G2+ data sources. The Starfix.G2+ satellite positioning service is particularly beneficial when seeking to measure latitude, longitude, elevation and speed with ultra-high accuracy in real-time.

Applications

Real-time correction of tidal changes - which impact the accuracy of seabed mapping

Real-time monitoring of the motion of floating and fixed structures.

The 3D accuracies of the system approach those of GNSS RTK (Real Time Kinematic) systems whilst avoiding the need for an RTK base station or local transmission link, overcoming the logistical challenges and range limitations associated with coastal RTK systems.

The resulting positional accuracies are better than 3cm and 6cm (2σ) in the horizontal and vertical planes respectively.

The Starfix.XP2 service is a GPS and GLONASS positioning system that is based on orbit and clock corrections obtained from a third party supplier. As with Starfix.G4,

Starfix.XP2 also utilises Precise Point Positioning (PPP) technology, and apart from that it is 100% independent to Starfix.G4. Further positional enhancements are undertaken in Fugro's software resulting in positional accuracies of better than 10cm and 20cm (2σ) in the horizontal and vertical planes respectively.

Our Starfix.L1 service utilises single frequency code correction data from the Fugro network of reference stations, delivered via L-Band satellite broadcasts. These corrections, combined with a single frequency GNSS receiver are used to produce a position of high accuracy. This system can provide a positional accuracy of better than 1.0 m (2σ) horizontally at a distance of 500 km from the nearest reference station.

Our StarfixNG Positioning Software is a state-of-the-art, logical and intuitive user interface. This software comprises a common framework which handles the vessel hardware configuration, a set of associated GNSS modules to undertake the computation and QC of the data and additional modules to support customer output formats. The software is modular which allows only the modules required for the task in hand are loaded.

StarfixNG MultiFix Solution

This is a GNSS position computation and QC routines packaged in a new windows framework. The computations are based on our state-of the-art EHF GNSS algorithms which are used to compute either high precision or standard precision solutions.

Key features

No limit on the number of correction system inputs.

No limit on the number of positional computations.

Each computation can employ corrections from any combination of reference stations.

StarfixNG GNSS Tides Solution

This computes real-time observed tides from GNSS data. Taking input from Starfix GNSS service, the module reduces positions to the vessel’s reference point by correcting for offsets and motion. This position is then heave and draft corrected to give height of calm sea above the ellipsoid. By use of a Mean Sea Surface model, the height above the ellipsoid can be reduced to a GNSS based tide value.

Key features

The vessel GNSS antenna height is derived via one of the Starfix high precision GNSS solutions.

The antenna height can be smoothed online using different filters.

Using the vessels antenna offset, motion sensor and draft, the height can be transferred to the vessel CRP to derive an ellipsoidal height for the CRP relative to the satellite positioning datum.

The CRP can then be referenced to MSL via mean sea surface model, of which two are included in the software at present:

The EGM2008 (earth gravitational model order 2160, global approximation of Mean Sea Surface). The accuracy of the model is about 20cm.

Our correction data are transmitted in a compressed and encrypted proprietary format known as SCF (Super Compressed Format). These corrections are available via High Power Satellite transmissions and via an NTRIP internet link (via the vessel VSAT system). The Fugro Correction Networks, Network Control Centres, Uplink Stations and Corrections Satellites are combined with independent vessel hardware and software to provide fully independent Starfix positioning solutions. In such a case there is no single point of failure which could cause both systems to fail.

Moving North

Operating in rough waters and in areas far away from other infrastructure and resources, like in the Arctic, requires the very best setup to ensure safe operations.

The standard method of correction data delivery is by broadcast over the Fugro network of L-Band geostationary communication satellites. This is an extremely reliable and robust system, but geostationary satellites, located above the equator, have a coverage footprint which is limited to around 70 deg North using standard spot beam antennas.

The combination of our unique purpose-made L-Band antenna for low elevation satellites (AD-493 receives corrections up to 75° North) and our NTRIP solution delivered over VSAT, ensures that you obtain the right corrections beyond the normal coverage to maintain reliable and safe operations in the Arctic

Iridium

To further improve the delivery of Starfix corrections in high latitudes and Polar Regions, we have developed a service to deliver these corrections via the Iridium Communications Open Port Service. Iridium is a satellite communications system of more than 60 satellites in Low Earth Polar Orbit (LEO), at an altitude of approximately 800 km. In order to deliver these corrections we have generated a dedicated NTRIP Service optimised for communications systems with limited band width. This service contains optimised Starfix.G2 orbit and clock corrections to allow vessels to obtain a precise GNSS PPP position.

As a result of a significant Fugro technology achievement, users of its G4 satellite correction service will be among the first in the world to benefit from Galileo’s much anticipated ‘initial services’ launch.

Fugro has further extended its technology leadership in the field of GNSS augmentation systems for offshore positioning applications with the launch of its G4 service. The new satellite correction service is the first to take advantage of all four GNSS (Global Navigation Satellite Systems): GPS, GLONASS, BeiDou and Galileo. GNSS augmentation services significantly improve position accuracy compared to unaided GNSS receivers, which are commonly used in the consumer sector.